Structural panel



Oct@ 31,y 1944. G. T. GERLACH [a1-A1.i

STRUCTURAL PANEL Filed July '21, 1941 3 Sheets-Sheet` l MME .mm

AM. bm,

Oct. 3l, 1,944.

Y G. T` GERLACH ETAL STRUCTURAL PANEL Filed July 21, 1941 3 Sheets-Sheet 2 Oct. 3l, 1944.

STRUCTURAL PANEL Filed July 21, 1941 3 Sheets-Sheet 5 Patented oer. 31, 1944 ign ascisse fsrarierpiear. raser.

Application July 21, 1941, Serial No.. @3,336 llllllaims. (Gl. :iSd-m34) The invention relates to metallic structural panels.

One object of the' invention is to provide a structural panel which comprises a thin metal skin-forming sheet and expanded metal havingY outstruclr portions serving as frame-members for stidening the panel for carrying transverse loads and resisting transverse bending.

Another object of the inventlon'is to provide a panel of this type which has a high strength- Weight ratio against transverse bending.

Other objects of the invention will appear from the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly definedby claims at the conclusion hereof.

h1 the drawings: Fig. 1 is a side elevation of a panel embodying the invention. Fig. 2 is an end view. Fig. 3 is a section on an enlarged scale `teiten cn line 3 3 of Fig. i. Fig. 4 is a perspective of a portion or the panel. Fig. 5 is a perspective of one or' the cap-plates at the corners of the border. Fig. 6 is a perspective of one of the cap-plates used at the intersections of the rows of il-shaped outstruck portions of the expanded metal. Fig. 7 is a perspective of one of the cap-plates between the ridge-strips and the loorderstrips. l Figq is a perspective of one of the strips on the arched portions of the expanded metal.A Fig. 9 is an enlarged fragmentary side elevation of the panel with some parts in dotted lines to show the structure underneath.

The invention is exemplified `in a rectangular panel which is adapted to be used as a part of the fuselage cf an airplane. The panel-is'huilt up primarily or" a sheet i@ of thinmetal for forming an outer vcovering or skin and attened diamond-mesh expanded metal i2 which is spotvvelded to the inner face of the sheet at a suiiicient number of points to support the 'sheet against transverse Yflexure. The expanded metal comprises bonds it and strands i5.' In practice, substantially all of the` bonds may he, spotvvelded, as at it, to the sheet but in some lnstances the welds :may be more Widely spaced apart. Eefore being welded to the sheet, the

' expanded metal is ilattened so that at least one of its faces will rit against the inner face of the sheet i6. A border for reinforcing the edges of the panel comprises strips il of thin sheet-metal which are spot-Welded to the margins of the sheet lil which project outwardly beyond the margins of the expanded metal l2. Each borderlstrip comprises a flange i8 around which the margin of the sheet iii is lapped, as at i9, to form a nished rim for the panel. Sheet it and flange it are spot-welded together, as at 2t. Each lcorcleiwstrip` it also'comprises artransversely extending or right-angled angetl and an inclined ange 22 which extends inwardly from the inner edge oi flanges 2 l and is inclined inwardly toward the sheet lil. The marginal portions of the expanded metal l2 are bent transversely and ohliquely away from sheet it to underlie the ianges 22 of the strips l1 and are spot-welded tothe inner face of said nanges.

These marginal portions of the expanded metal support the inner edges of the border-strips and reinforce them to render the border of the panel rigid in substantially all directions. Cornerplates or gussets i5 are welded to the outer inclined face of the flanges 22 at the meeting corners of the border-strips- Each plate 25 'comprises inclined iianges @it iitting the adjacent inner faces of anges 22, a triangular member 25a, and an inturned flange il extending diagonally across a corner of the panel transversely inward. This exemplifies a panel comprising a .skin-forming sheet and expanded metal bonded 'together and a border-construction which stlffens the panel and renders it transversely andlongitudinally rigid. The panel may be flat or may he of arcuate contour, as illustrated in Fig. 2.

in practice it has heen found that a panel composed of a sheet .007 in thickness and diamond-mesh expanded rnetal with a long axis of 3.25" and a short axis L56 and the strands approximately 135e in. thickness without regard to the reinforcement of the border have greater transverse strength than aluminum .932" in thickness and that the weight of the composite structure will .be no greater than that of the aluminum. It is advantageous to .use ferrous metal on account of itsv lowcost. The bondingy of the expandedl metal to the border makes it possible to produce a marginally rigid panel with a thin skin-forming sheet reinforced by the expanded metal. The stiffening border, deformations of the expanded metal and the strips when bonded together function as framing which also has a high strength-.Weight ratio.

The invention exemplifies a metal panel which comprises' a skin-forming sheet, expanded metal bonded to the sheet.. and aborder composedl of strips bonded to the expanded metal and to the sheet, which results in a panel with a high strength-weight ratio. i The invention also exempliiies a frame-like reinforcement for the panel which comprises arched integral portions of the expanded metal and rigidly connected by ridge- I strips which function as frame-members for providing vthe required .strength for variousloads strands of the latter may be welded, as at 23h. All parts of the panel will then be rigidly connected to form a panel of a high strength-weight ratio and adapted for transverse and longitudinal loading and for resisting torsional and shear stresses when the panel is in use.

The invention is not to be understood as restricted to the details set forth, since these may be modiiied within the scope of the appended claims, without departing from the spirit and y scope of the invention.

frame-members which comprise rows of V -shaped f or arched portions of the expanded metal. These rows extend crosswise of one another or longitudinally and transversely of the panel and are sufficient in number to stien the panel throughout its area within the border. Before the expanded metal l2' is bonded to the sheet Il) it is bent to form a longitudinal row of V-shaped or arched portions 30 which extend transversely away from the sheet ID and rows of V-shaped' or arched portions 3| which extend crosswise of the-longitudinal row of V-shaped portions 30. Longitudinally extending strips 32, which are V- shaped in cross-section iit over the apices of the V-shaped portions 30 between' the crosswise rowsl 3| and the border-strips, are spot-welded thereto, and form rigid strips which connect series of` said V-shaped portions 30 in the longitudinal row. Similarly V-shaped` strips 33 extend over,v

are spot-welded to, and form ridge-strips which rigidly connect the series of the apices of the V-shaped portions 3| in the transverse rows between the border and the longitudinal row of V-shaped portions 3l). At the intersections of the longitudinal and crosswise rows of the V- shaped portions 30, 3| a cap-plate 34 is spotwelded to the adjacent ends of the ridge-strips 32 and 33 to rigidly connect said strips at the intersections of the rows. The cap-plate 34 comprises iour members 34e, V-shaped in cross-section to conform to the V-shaped faces of the strips 32 and 33. The ends of the ridge-strips 32 and 33 are each rigidly connected to the border by.a cap-plate 31 which comprises a V-shaped member 38 conforming to one face of the ridgestrip, an inclined ilange 39 conforming to the flange 22 of the border-strips I1 and transverse flanges 40. The flanges 39 are spot-Welded to ilanges 22 and the V-shaped member 38 is spotwelded to the apices of the V-.shaped portions in the expanded metal.

In fabricating the panel the expanded metal, after it has been flattened, is bent in suitable dies to form rows of V-shaped portions 30, 3| and its marginal portions 23 are also bent, before any of the parts are Welded thereto. The ridge-strips 32, 33 are next welded tothe V- Ashaped portions 30, 3| of the expanded metal and plates`34, 31 are welded to stripsy 32, 33.

Having thus described Vthe invention, ywhat we claim as new and desire to secure by Letters Patent is:

1. A structural panel comprising flattened expanded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the yexpanded metal, the expanded metal having a row of `integral arched portions extending away from the sheet, and a strip of metal bonded to and connecting the arched portions.

2. A structural panel comprising attened expanded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, the expanded metal having a row of integral substantially V-shaped portions extending away from the sheet, and a strip substantially V-shaped in cross-section bonded to and rigidly connecting the apices of the arched portions.

3. A structural panel comprising attened expanded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, the expanded metal having rows extending crosswise of one another of integral arched portions extending away from the sheet, and strips bonded to and rigidly connecting the apices of the arched portions in the rows respectively. l

4. A structural panel comprising flattened expanded metal, a thinskin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, the expanded metal having rowsl extending crosswise of one another of integral arched portions extending away from the sheet,- strips bonded to and rigidly connecting the apices of the arched portions of the rows, respectively, and plates at and bonded to the strips at the intersections of the rows.

5. A structural panel"comprising flattened expanded diamond-mesh metal, a thin skin-forming sheet of metal bonded at points distributed lthroughout the area of the expanded metal, a

l idly connecting the apices of the arched portions,

Next, the bent portions 23 at the margins of the expanded metal are welded to the flanges 22 and the corner-plates 25. The expanded metal and border-strips are assembled with the sheet |0 by folding vthe flange I9 of the sheet over vthe anges I8 of the border-strips andv the expanded metal is spot-welded, preferably at the bonds,"to the-'sheet I0'. Adjacent the rows of V-shaped portions of theexpanded metal the and secured to the border.

6. A structural panel comprising flattened expanded metal, a thin skin-forming sheet of metal bonded to and throughout the area of the expanded metal, and a, border of metal extending from the sheet and being bonded to the ange of the border-strip along a line spaced transversely from the sheet.

8. A structural panel comprising flattened expanded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, and a border of metal extending around the margin of the sheet and comprising'av strip having a flange extending transversely away .from the sheet and a ange around which the margin of the sheet is folded, the margin of the expanded metal extending away from the sheet and being bonded to the strip along a line spaced from the sheet.

9. A structural panel comprising attened ex panded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, a border of metal extending around and secured to the margin of the sheet and comprising a ange extending transversely away from the sheet and an lnturned flange, the margin of the expanded metal being bonded to the inner face of the inturned ange along a line spaced from the sheet.

10. A structural panel comprising flattened expanded metal, a thin skin-lo sheet or metal bonded at points distributed throughout the area of the expanded metal, a border extending around and secured to the margin of the sheet and cornprising a flange extending transversely away from the sheet, the expanded metal having rows of arched portions between the border and ridgestrips bonded to the archedy portions, and to the border.

11. A structural panel comprising flattened expanded metal, a thin skin-forming sheet of metal bonded at points distributed throughout the area of the expanded metal, and a border of metal having a iiange extending transversely away from the sheet, the marginal portion of the expanded metal extending transversely away from the sheet and being bonded to the border-member, the expanded metal having rows extending crosswse of one another of arched portions extending away from the sheet, strips bonded to arched portions, plates bonded to the strips at the intersection of the rows, and plates bonded to the strips and to the border.

GIENDQN 'I'. GEBLACH. PETER ALTMAN. 1.. i .S. KOS. 

